bug report: receiving address checked against LDAP 

### 📝 Preliminary Checks

- [X] I tried searching for an existing issue and followed the [debugging docs](https://docker-mailserver.github.io/docker-mailserver/latest/config/debugging/) advice, but still need assistance.

### 👀 What Happened?

Today I converted my docker-mailserver to use LDAP as authentication mechanism.
Receiving mails works well, from outside (e.g. @gmail.com and inside @melijn.com).
Sending email between internal users (@melijn.com) works.
**Sending emails to mailboxes outside (e.g. @gmail.com does not).**

I did not see any mention of configuration to which addresses you can send to unless I misunderstood the docs: https://docker-mailserver.github.io/docker-mailserver/latest/config/advanced/auth-ldap/.

### 👟 Reproduction Steps

Env: [mail-server.env.txt](https://github.com/docker-mailserver/docker-mailserver/files/12622664/mail-server.env.txt)

LDAP Search query: 
```
I have no name!@d0d034e122f5:/$ ldapsearch -x -H ldaps://ldap.melijn.com -b 'dc=melijn,dc=com' -D "cn=admin,dc=melijn,dc=com" -W "(&(objectClass=inetOrgPerson)(mail=merlijn@melijn.com))"
```
```
# extended LDIF
#
# LDAPv3
# base <dc=melijn,dc=com> with scope subtree
# filter: (&(objectClass=inetOrgPerson)(mail=merlijn@melijn.com))
# requesting: ALL
#

# merlijn, users, melijn.com
dn: cn=merlijn,ou=users,dc=melijn,dc=com
givenName: redacted1
sn: redacted2
cn: merlijn
uid: merlijn
uidNumber: 1002
gidNumber: 500
homeDirectory: /home/users/merlijn
objectClass: inetOrgPerson
objectClass: posixAccount
objectClass: top
mail: merlijn@melijn.com
userPassword:: redacted

# search result
search: 2
result: 0 Success

# numResponses: 2
# numEntries: 1
```

### 🐋 DMS Version

v12.1.0

### 💻 Operating System and Architecture

5.4.0-162-generic #179-Ubuntu

### ⚙️ Container configuration files

```yml
version: '3.7'

services:
  mail:
    image: mailserver/docker-mailserver:latest
    hostname: mail
    domainname: melijn.com
    container_name: mail
    ports:
      - "25:25"
      - "143:143"
      - "587:587"
      - "993:993"
    volumes:
      - maildata:/var/mail
      - mailstate:/var/mail-state
      - maillogs:/var/log/mail
      - ./config/:/tmp/docker-mailserver/
      - /opt/traefik/acme.json:/etc/letsencrypt/acme.json:ro
    env_file:
      - .env
      - mail-server.env
    networks:
      - proxy_default
    cap_add:
      - NET_ADMIN
      - SYS_PTRACE
    restart: always

  nginx2:
    image: nginx:latest
    container_name: "gen-nginx-mail-cert"
    volumes:
      - /data/www/:/usr/share/nginx/html/
    networks:
      - proxy_default
    labels:
      - "traefik.http.routers.certgen.rule=Host(`mail.melijn.com`)"
      - "traefik.enable=true"
      - "traefik.http.services.certgen.loadbalancer.server.port=80"
      - "traefik.http.routers.certgen.tls=true"
      - "traefik.http.routers.certgen.entrypoints=websecure"
      - "traefik.http.routers.certgen.tls.certresolver=le"

networks:
  proxy_default:
    external: true

volumes:
  maildata:
  mailstate:
  maillogs:
```


### 📜 Relevant log output

```Text
mail                 | Sep 15 18:35:25 mail postfix/submission/smtpd[1005]: connect from 113.168-65-87.adsl-dyn.isp.belgacom.be[87.65.168.113]
mail                 | Sep 15 18:35:26 mail postfix/submission/smtpd[1005]: Anonymous TLS connection established from 113.168-65-87.adsl-dyn.isp.belgacom.be[87.65.168.113]: TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256
mail                 | Sep 15 18:35:26 mail dovecot: imap-login: Login: user=<merlijn>, method=PLAIN, rip=127.0.0.1, lip=127.0.0.1, mpid=1010, secured, session=<dTRgDmoFwIN/AAAB>
mail                 | Sep 15 18:35:26 mail dovecot: imap(merlijn)<1010><dTRgDmoFwIN/AAAB>: Disconnected: Logged out in=16 out=496 deleted=0 expunged=0 trashed=0 hdr_count=0 hdr_bytes=0 body_count=0 body_bytes=0
mail                 | Sep 15 18:35:26 mail postfix/submission/smtpd[1005]: 3F8FA227F4: client=113.168-65-87.adsl-dyn.isp.belgacom.be[87.65.168.113], sasl_method=PLAIN, sasl_username=merlijn@melijn.com
mail                 | Sep 15 18:35:26 mail postfix/sender-cleanup/cleanup[1012]: 3F8FA227F4: message-id=<a1351c88-8e7b-4fb6-bca1-53b455f05475@melijn.com>
mail                 | Sep 15 18:35:26 mail postfix/sender-cleanup/cleanup[1012]: 3F8FA227F4: replace: header MIME-Version: 1.0 from 113.168-65-87.adsl-dyn.isp.belgacom.be[87.65.168.113]; from=<merlijn@melijn.com> to=<pixelhamsteryt@gmail.com> proto=ESMTP helo=<[192.168.1.33]>: MIME-Version: 1.0
mail                 | Sep 15 18:35:26 mail opendkim[873]: 3F8FA227F4: DKIM-Signature field added (s=mail, d=melijn.com)
mail                 | Sep 15 18:35:26 mail postfix/qmgr[985]: 3F8FA227F4: from=<merlijn@melijn.com>, size=374, nrcpt=1 (queue active)
mail                 | Sep 15 18:35:26 mail dovecot: imap-login: Login: user=<merlijn>, method=PLAIN, rip=87.65.168.113, lip=172.18.0.25, mpid=1016, TLS, session=<NQJnDmoFDLJXQahx>
mail                 | Sep 15 18:35:26 mail dovecot: imap(merlijn)<1016><NQJnDmoFDLJXQahx>: Disconnected: Logged out in=464 out=624 deleted=0 expunged=0 trashed=0 hdr_count=0 hdr_bytes=0 body_count=0 body_bytes=0
mail                 | Sep 15 18:35:27 mail postfix/smtpd-amavis/smtpd[1018]: connect from localhost[127.0.0.1]
mail                 | Sep 15 18:35:27 mail postfix/smtpd-amavis/smtpd[1018]: E33D722F63: client=localhost[127.0.0.1]
mail                 | Sep 15 18:35:27 mail postfix/cleanup[1019]: E33D722F63: message-id=<a1351c88-8e7b-4fb6-bca1-53b455f05475@melijn.com>
mail                 | Sep 15 18:35:27 mail postfix/qmgr[985]: E33D722F63: from=<merlijn@melijn.com>, size=1083, nrcpt=1 (queue active)
mail                 | Sep 15 18:35:27 mail amavis[1003]: (01003-01) Passed CLEAN {RelayedOpenRelay}, [87.65.168.113]:54144 [87.65.168.113] <merlijn@melijn.com> -> <pixelhamsteryt@gmail.com>, Queue-ID: 3F8FA227F4, Message-ID: <a1351c88-8e7b-4fb6-bca1-53b455f05475@melijn.com>, mail_id: h6HUMdGGE7aH, Hits: -0.202, size: 871, queued_as: E33D722F63, 1602 ms
mail                 | Sep 15 18:35:27 mail postfix/smtp-amavis/smtp[1013]: 3F8FA227F4: to=<pixelhamsteryt@gmail.com>, relay=127.0.0.1[127.0.0.1]:10024, delay=1.7, delays=0.13/0.01/0.01/1.6, dsn=2.0.0, status=sent (250 2.0.0 from MTA(smtp:[127.0.0.1]:10025): 250 2.0.0 Ok: queued as E33D722F63)
mail                 | Sep 15 18:35:27 mail postfix/qmgr[985]: 3F8FA227F4: removed
mail                 | Sep 15 18:35:27 mail dovecot: lmtp(1021): Connect from local
mail                 | Sep 15 18:35:27 mail dovecot: auth: ldap(pixelhamsteryt@gmail.com): unknown user
mail                 | Sep 15 18:35:27 mail postfix/lmtp[1020]: E33D722F63: to=<pixelhamsteryt@gmail.com>, relay=mail.melijn.com[/var/run/dovecot/lmtp], delay=0.06, delays=0.03/0.02/0.01/0.01, dsn=5.1.1, status=bounced (host mail.melijn.com[/var/run/dovecot/lmtp] said: 550 5.1.1 <pixelhamsteryt@gmail.com> User doesn't exist: pixelhamsteryt@gmail.com (in reply to RCPT TO command))
mail                 | Sep 15 18:35:27 mail dovecot: lmtp(1021): Disconnect from local: Logged out (state=READY)
mail                 | Sep 15 18:35:27 mail postfix/cleanup[1019]: F0B9522F6C: message-id=<20230915183527.F0B9522F6C@mail.melijn.com>
mail                 | Sep 15 18:35:27 mail postfix/qmgr[985]: F0B9522F6C: from=<>, size=3132, nrcpt=1 (queue active)
mail                 | Sep 15 18:35:27 mail postfix/bounce[1022]: E33D722F63: sender non-delivery notification: F0B9522F6C
mail                 | Sep 15 18:35:27 mail postfix/qmgr[985]: E33D722F63: removed
mail                 | Sep 15 18:35:27 mail dovecot: lmtp(1021): Connect from local
mail                 | Sep 15 18:35:28 mail dovecot: lmtp(merlijn@melijn.com)<1021><aIdIO++jBGX9AwAADnb+Ww>: sieve: msgid=<20230915183527.F0B9522F6C@mail.melijn.com>: stored mail into mailbox 'INBOX'
mail                 | Sep 15 18:35:28 mail postfix/lmtp[1020]: F0B9522F6C: to=<merlijn@melijn.com>, relay=mail.melijn.com[/var/run/dovecot/lmtp], delay=0.02, delays=0.01/0/0/0.01, dsn=2.0.0, status=sent (250 2.0.0 <merlijn@melijn.com> aIdIO++jBGX9AwAADnb+Ww Saved)
mail                 | Sep 15 18:35:28 mail postfix/qmgr[985]: F0B9522F6C: removed
mail                 | Sep 15 18:35:28 mail dovecot: lmtp(1021): Disconnect from local: Logged out (state=READY)
```
```
6504a3ef.37b599b7 0x7fdf9cbfb700 conn=1217 op=0 STARTTLS
6504a3ef.37b726e9 0x7fdf9cbfb700 conn=1217 op=0 RESULT oid= err=0 qtime=0.000014 etime=0.000147 text=
6504a3ef.3848a535 0x7fdfaec9d700 conn=1217 fd=17 TLS established tls_ssf=256 ssf=256 tls_proto=TLSv1.3 tls_cipher=TLS_AES_256_GCM_SHA384
6504a3ef.3868ba21 0x7fdfae49c700 conn=1217 op=1 BIND dn="cn=admin,dc=melijn,dc=com" method=128
6504a3ef.386c6bdf 0x7fdfae49c700 conn=1217 op=1 BIND dn="cn=admin,dc=melijn,dc=com" mech=SIMPLE bind_ssf=0 ssf=256
6504a3ef.387063e8 0x7fdfae49c700 conn=1217 op=1 RESULT tag=97 err=0 qtime=0.000017 etime=0.000565 text=
6504a3ef.3872e2db 0x7fdf9d3fc700 connection_input: conn=1217 deferring operation: binding
6504a3ef.3875e04b 0x7fdfae49c700 conn=1217 op=2 SRCH base="dc=melijn,dc=com" scope=2 deref=0 filter="(&(objectClass=inetOrgPerson)(?mailAlias=pixelhamsteryt@gmail.com))"
6504a3ef.3877bc3d 0x7fdfae49c700 conn=1217 op=2 SRCH attr=mail
6504a3ef.3879b6d3 0x7fdfae49c700 conn=1217 op=2 SEARCH RESULT tag=101 err=0 qtime=0.000173 etime=0.000447 nentries=0 text=
6504a3ef.387f4772 0x7fdf9edfe700 conn=1217 op=3 SRCH base="dc=melijn,dc=com" scope=2 deref=0 filter="(&(objectClass=inetOrgPerson)(?mailGroupMember=pixelhamsteryt@gmail.com))"
6504a3ef.3880469f 0x7fdf9edfe700 conn=1217 op=3 SRCH attr=mail
6504a3ef.3882fee8 0x7fdf9edfe700 conn=1217 op=3 SEARCH RESULT tag=101 err=0 qtime=0.000018 etime=0.000278 nentries=0 text=
6504a3ef.3888889a 0x7fdfaec9d700 conn=1217 op=4 SRCH base="dc=melijn,dc=com" scope=2 deref=0 filter="(&(objectClass=inetOrgPerson)(?mailAlias=@gmail.com))"
6504a3ef.3888f4e5 0x7fdfaec9d700 conn=1217 op=4 SRCH attr=mail
6504a3ef.388b3c9e 0x7fdfaec9d700 conn=1217 op=4 SEARCH RESULT tag=101 err=0 qtime=0.000017 etime=0.000230 nentries=0 text=
6504a3ef.38900a9d 0x7fdf9d3fc700 conn=1217 op=5 SRCH base="dc=melijn,dc=com" scope=2 deref=0 filter="(&(objectClass=inetOrgPerson)(?mailGroupMember=@gmail.com))"
6504a3ef.3890982c 0x7fdf9d3fc700 conn=1217 op=5 SRCH attr=mail
6504a3ef.38919a66 0x7fdf9d3fc700 conn=1217 op=5 SEARCH RESULT tag=101 err=0 qtime=0.000015 etime=0.000138 nentries=0 text=
6504a3ef.38af333b 0x7fdf9cbfb700 conn=1215 op=12 SRCH base="dc=melijn,dc=com" scope=2 deref=0 filter="(&(objectClass=inetOrgPerson)(?mailAlias=gmail.com))"
6504a3ef.38b02066 0x7fdf9cbfb700 conn=1215 op=12 SRCH attr=mail
6504a3ef.38b2f6dc 0x7fdf9cbfb700 conn=1215 op=12 SEARCH RESULT tag=101 err=0 qtime=0.000015 etime=0.000283 nentries=0 text=
6504a3ef.38d233bf 0x7fdfae49c700 conn=1215 op=13 SRCH base="dc=melijn,dc=com" scope=2 deref=0 filter="(&(objectClass=inetOrgPerson)(?mailGroupMember=gmail.com))"
6504a3ef.38d67ec0 0x7fdfae49c700 conn=1215 op=13 SRCH attr=mail
6504a3ef.38d9c769 0x7fdfae49c700 conn=1215 op=13 SEARCH RESULT tag=101 err=0 qtime=0.000021 etime=0.000538 nentries=0 text=
6504a3ef.38dff81b 0x7fdf9edfe700 conn=1215 op=14 SRCH base="dc=melijn,dc=com" scope=2 deref=0 filter="(mail=*@gmail.com)"
6504a3ef.38e0bf31 0x7fdf9edfe700 conn=1215 op=14 SRCH attr=mail
6504a3ef.38e49388 0x7fdf9edfe700 conn=1215 op=14 SEARCH RESULT tag=101 err=0 qtime=0.000018 etime=0.000331 nentries=1 text=
6504a3ef.3a4586dc 0x7fdfaec9d700 conn=1214 op=8 SRCH base="dc=melijn,dc=com" scope=2 deref=0 filter="(&(objectClass=inetOrgPerson)(uid=pixelhamsteryt))"
6504a3ef.3a46f557 0x7fdfaec9d700 conn=1214 op=8 SRCH attr=uid gidNumber
6504a3ef.3a4afd7e 0x7fdfaec9d700 conn=1214 op=8 SEARCH RESULT tag=101 err=0 qtime=0.000030 etime=0.000429 nentries=0 text=
6504a3ef.3ad4ed41 0x7fdf9d3fc700 conn=1217 op=6 SRCH base="dc=melijn,dc=com" scope=2 deref=0 filter="(&(objectClass=inetOrgPerson)(?mailAlias=merlijn@melijn.com))"
6504a3ef.3ad5df8c 0x7fdf9d3fc700 conn=1217 op=6 SRCH attr=mail
```
```


### Improvements to this form?

_No response_

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

bug report: receiving address checked against LDAP #3538

📝 Preliminary Checks

👀 What Happened?

👟 Reproduction Steps

🐋 DMS Version

💻 Operating System and Architecture

⚙️ Container configuration files

📜 Relevant log output

Metadata

Assignees

Labels

Type

Projects

Milestone

Relationships

Development

Uh oh!

bug report: receiving address checked against LDAP #3538

Description

📝 Preliminary Checks

👀 What Happened?

👟 Reproduction Steps

🐋 DMS Version

💻 Operating System and Architecture

⚙️ Container configuration files

📜 Relevant log output

Metadata

Metadata

Assignees

Labels

Type

Projects

Milestone

Relationships

Development

Issue actions